rxvt-unicode/src/ptytty.C

/*--------------------------------*-C-*---------------------------------*
 * File:        ptytty.C
 *----------------------------------------------------------------------*
 *
 * All portions of code are copyright by their respective author/s.
 * Copyright (c) 1999-2001 Geoff Wing <gcw@pobox.com>
 * Copyright (c) 2004-2006 Marc Lehmann <pcg@goof.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *---------------------------------------------------------------------*/

#include "../config.h"          /* NECESSARY */
#include "rxvt.h"

#include <cstdlib>
#include <cstring>

#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <fcntl.h>

#ifdef HAVE_SYS_IOCTL_H
# include <sys/ioctl.h>
#endif
#if defined(PTYS_ARE_PTMX) && defined(HAVE_SYS_STROPTS_H)
# include <sys/stropts.h>      /* for I_PUSH */
#endif
#ifdef HAVE_ISASTREAM
# include <stropts.h>
#endif
#if defined(HAVE_PTY_H)
# include <pty.h>
#elif defined(HAVE_LIBUTIL_H)
# include <libutil.h>
#elif defined(HAVE_UTIL_H)
# include <util.h>
#endif

#include <cstdio>
#include <grp.h>

#include "rxvtutil.h"
#include "fdpass.h"
#include "ptytty.h"

/////////////////////////////////////////////////////////////////////////////

/* ------------------------------------------------------------------------- *
 *                  GET PSEUDO TELETYPE - MASTER AND SLAVE                   *
 * ------------------------------------------------------------------------- */
/*
 * Returns pty file descriptor, or -1 on failure 
 * If successful, ttydev is set to the name of the slave device.
 * fd_tty _may_ also be set to an open fd to the slave device
 */
static inline int
get_pty_streams (int *fd_tty, char **ttydev)
{
#ifdef NO_SETOWNER_TTYDEV
  int pfd;

# if defined(PTYS_ARE_GETPT)
  pfd = getpt();
# elif defined(PTYS_ARE_POSIX)
  pfd = posix_openpt (O_RDWR);
# else
  pfd = open ("/dev/ptmx", O_RDWR | O_NOCTTY, 0);
# endif
  if (pfd >= 0)
    {
      if (grantpt (pfd) == 0    /* change slave permissions */
          && unlockpt (pfd) == 0)
        {       /* slave now unlocked */
          *ttydev = strdup (ptsname (pfd));     /* get slave's name */
          return pfd;
        }

      close (pfd);
    }
#endif

  return -1;
}

static inline int
get_pty_openpty (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_OPENPTY
  int pfd;
  int res;
  char tty_name[sizeof "/dev/pts/????\0"];
  
  res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
  if (res != -1)
    {
      *ttydev = strdup (tty_name);
      return pfd;
    }
#endif

  return -1;
}

static inline int
get_pty__getpty (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE__GETPTY
  int pfd;

  *ttydev = _getpty (&pfd, O_RDWR | O_NONBLOCK | O_NOCTTY, 0622, 0);
  if (*ttydev != NULL)
    return pfd;
#endif

  return -1;
}

static inline int
get_pty_ptc (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_PTC
  int pfd;

  if ((pfd = open ("/dev/ptc", O_RDWR | O_NOCTTY, 0)) >= 0)
    {
      *ttydev = strdup (ttyname (pfd));
      return pfd;
    }
#endif

  return -1;
}

static inline int
get_pty_clone (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_CLONE
  int pfd;

  if ((pfd = open ("/dev/ptym/clone", O_RDWR | O_NOCTTY, 0)) >= 0)
    {
      *ttydev = strdup (ptsname (pfd));
      return pfd;
    }
#endif

  return -1;
}

static inline int
get_pty_numeric (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_NUMERIC
  int pfd;
  int idx;
  char *c1, *c2;
  char pty_name[] = "/dev/ptyp???";
  char tty_name[] = "/dev/ttyp???";

  c1 = &(pty_name[sizeof (pty_name) - 4]);
  c2 = &(tty_name[sizeof (tty_name) - 4]);

  for (idx = 0; idx < 256; idx++)
    {
      sprintf (c1, "%d", idx);
      sprintf (c2, "%d", idx);

      if (access (tty_name, F_OK) < 0)
        {
          idx = 256;
          break;
        }

      if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) >= 0)
        {
          if (access (tty_name, R_OK | W_OK) == 0)
            {
              *ttydev = strdup (tty_name);
              return pfd;
            }

          close (pfd);
        }
    }
#endif

  return -1;
}

static inline int
get_pty_searched (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_SEARCHED
# ifndef PTYCHAR1
#  define PTYCHAR1      "pqrstuvwxyz"
# endif
# ifndef PTYCHAR2
#  define PTYCHAR2      "0123456789abcdef"
# endif
  int pfd;
  const char *c1, *c2;
  char pty_name[] = "/dev/pty??";
  char tty_name[] = "/dev/tty??";

  for (c1 = PTYCHAR1; *c1; c1++)
    {
      pty_name[ (sizeof (pty_name) - 3)] =
        tty_name[ (sizeof (pty_name) - 3)] = *c1;

      for (c2 = PTYCHAR2; *c2; c2++)
        {
          pty_name[ (sizeof (pty_name) - 2)] =
            tty_name[ (sizeof (pty_name) - 2)] = *c2;

          if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) >= 0)
            {
              if (access (tty_name, R_OK | W_OK) == 0)
                {
                  *ttydev = strdup (tty_name);
                  return pfd;
                }

              close (pfd);
            }
        }
    }
#endif

  return -1;
}

static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

  if ((pfd = get_pty_streams (fd_tty, ttydev)) != -1
      || (pfd = get_pty_openpty (fd_tty, ttydev)) != -1
      || (pfd = get_pty__getpty (fd_tty, ttydev)) != -1
      || (pfd = get_pty_ptc (fd_tty, ttydev)) != -1
      || (pfd = get_pty_clone (fd_tty, ttydev)) != -1
      || (pfd = get_pty_numeric (fd_tty, ttydev)) != -1
      || (pfd = get_pty_searched (fd_tty, ttydev)) != -1)
    return pfd;

  return -1;
}

/*----------------------------------------------------------------------*/
/*
 * Returns tty file descriptor, or -1 on failure 
 */
static int
get_tty (char *ttydev)
{
  return open (ttydev, O_RDWR | O_NOCTTY, 0);
}

/*----------------------------------------------------------------------*/
/*
 * Make our tty a controlling tty so that /dev/tty points to us
 */
static int
control_tty (int fd_tty)
{
  setsid ();

#if defined(PTYS_ARE_PTMX) && defined(I_PUSH)
  /*
   * Push STREAMS modules:
   *    ptem: pseudo-terminal hardware emulation module.
   *    ldterm: standard terminal line discipline.
   *    ttcompat: V7, 4BSD and XENIX STREAMS compatibility module.
   *
   * After we push the STREAMS modules, the first open () on the slave side
   * (i.e. the next section between the dashes giving us "tty opened OK")
   * should make the "ptem" (or "ldterm" depending upon either which OS
   * version or which set of manual pages you have) module give us a
   * controlling terminal.  We must already have close ()d the master side
   * fd in this child process before we push STREAMS modules on because the
   * documentation is really unclear about whether it is any close () on
   * the master side or the last close () - i.e. a proper STREAMS dismantling
   * close () - on the master side which causes a hang up to be sent
   * through - Geoff Wing
   */
# ifdef HAVE_ISASTREAM
  if (isastream (fd_tty) == 1)
# endif
    {
      ioctl (fd_tty, I_PUSH, "ptem");
      ioctl (fd_tty, I_PUSH, "ldterm");
      ioctl (fd_tty, I_PUSH, "ttcompat");
    }
#endif

  ioctl (fd_tty, TIOCSCTTY, NULL);

  int fd = open ("/dev/tty", O_WRONLY);
  if (fd < 0)
    return -1;          /* fatal */

  close (fd);

  return 0;
}

void
rxvt_ptytty::close_tty ()
{
  if (tty < 0)
    return;

  close (tty);
  tty = -1;
}

bool
rxvt_ptytty::make_controlling_tty ()
{
  return control_tty (tty) >= 0;
}

void
rxvt_ptytty::set_utf8_mode (bool on)
{
#ifdef IUTF8
  if (pty < 0)
    return;

  struct termios tio;

  if (tcgetattr (pty, &tio) != -1)
    {
      tcflag_t new_cflag = tio.c_iflag;

      if (on)
        new_cflag |= IUTF8;
      else
        new_cflag &= ~IUTF8;

      if (new_cflag != tio.c_iflag)
        {
          tio.c_iflag = new_cflag;
          tcsetattr (pty, TCSANOW, &tio);
        }
    }
#endif
}

/////////////////////////////////////////////////////////////////////////////

#ifndef NO_SETOWNER_TTYDEV
static struct ttyconf {
  gid_t gid;
  mode_t mode;

  ttyconf ()
    {
#ifdef TTY_GID_SUPPORT
      struct group *gr = getgrnam ("tty");

      if (gr)
        {           /* change group ownership of tty to "tty" */
          mode = S_IRUSR | S_IWUSR | S_IWGRP;
          gid = gr->gr_gid;
        }
      else
#endif                          /* TTY_GID_SUPPORT */
        {
          mode = S_IRUSR | S_IWUSR | S_IWGRP | S_IWOTH;
          gid = 0;
        }
    }
} ttyconf;

/////////////////////////////////////////////////////////////////////////////

void
rxvt_ptytty_unix::privileges (rxvt_privaction action)
{
  if (!name || !*name)
    return;

  if (action == SAVE)
    {
      chown (name, getuid (), ttyconf.gid);      /* fail silently */
      chmod (name, ttyconf.mode);
# ifdef HAVE_REVOKE
      revoke (name);
# endif
    }
  else
    {                    /* action == RESTORE */
      chmod (name, RESTORE_TTY_MODE);
      chown (name, 0, ttyconf.gid);
    }
}
#endif

rxvt_ptytty_unix::rxvt_ptytty_unix ()
{
  pty = tty = -1;
  name = 0;
#if UTMP_SUPPORT
  cmd_pid = 0;
#endif
}

rxvt_ptytty_unix::~rxvt_ptytty_unix ()
{
#if UTMP_SUPPORT
  logout ();
#endif
  put ();
}

void
rxvt_ptytty_unix::put ()
{
#ifndef NO_SETOWNER_TTYDEV
  privileges (RESTORE);
#endif

  if (pty >= 0) close (pty);
  close_tty ();
  free (name);

  pty = tty = -1;
  name = 0;
}

bool
rxvt_ptytty_unix::get ()
{
  /* get master (pty) */
  if ((pty = get_pty (&tty, &name)) < 0)
    return false;

  fcntl (pty, F_SETFL, O_NONBLOCK);

  /* get slave (tty) */
  if (tty < 0)
    {
#ifndef NO_SETOWNER_TTYDEV
      privileges (SAVE);
#endif

      if ((tty = get_tty (name)) < 0)
        {
          put ();
          return false;
        }
    }

  return true;
}

#if PTYTTY_HELPER

static int sock_fd;
static int pid;

struct command
{
  enum { get, login, destroy } type;

  rxvt_ptytty *id;

  bool login_shell;
  int cmd_pid;
  char hostname[512]; // arbitrary, but should be plenty
};

struct rxvt_ptytty_proxy : zero_initialized, rxvt_ptytty
{
  rxvt_ptytty *id;

  ~rxvt_ptytty_proxy ();

  bool get ();
  void login (int cmd_pid, bool login_shell, const char *hostname);
};

bool
rxvt_ptytty_proxy::get ()
{
  command cmd;

  cmd.type = command::get;

  write (sock_fd, &cmd, sizeof (cmd));

  if (read (sock_fd, &id, sizeof (id)) != sizeof (id))
    rxvt_fatal ("protocol error while creating pty using helper process, aborting.\n");

  if (!id)
    return false;

  if ((pty = rxvt_recv_fd (sock_fd)) < 0
      || (tty = rxvt_recv_fd (sock_fd)) < 0)
    rxvt_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n");

  return true;
}

void
rxvt_ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname)
{
  command cmd;

  cmd.type = command::login;
  cmd.id = id;
  cmd.cmd_pid = cmd_pid;
  cmd.login_shell = login_shell;
  strncpy (cmd.hostname, hostname, sizeof (cmd.hostname));

  write (sock_fd, &cmd, sizeof (cmd));
}

rxvt_ptytty_proxy::~rxvt_ptytty_proxy ()
{
  command cmd;

  cmd.type = command::destroy;
  cmd.id = id;

  write (sock_fd, &cmd, sizeof (cmd));
}

static
void serve ()
{
  command cmd;
  vector<rxvt_ptytty *> ptys;

  while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command))
    {
      if (cmd.type == command::get)
        {
          // -> id ptyfd ttyfd
          cmd.id = new rxvt_ptytty_unix;

          if (cmd.id->get ())
            {
              write (sock_fd, &cmd.id, sizeof (cmd.id));
              ptys.push_back (cmd.id);

              rxvt_send_fd (sock_fd, cmd.id->pty);
              rxvt_send_fd (sock_fd, cmd.id->tty);
            }
          else
            {
              delete cmd.id;
              cmd.id = 0;
              write (sock_fd, &cmd.id, sizeof (cmd.id));
            }
        }
      else if (cmd.type == command::login)
        {
#if UTMP_SUPPORT
          if (find (ptys.begin (), ptys.end (), cmd.id))
            {
              cmd.hostname[sizeof (cmd.hostname) - 1] = 0;
              cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname);
            }
#endif
        }
      else if (cmd.type == command::destroy)
        {
          rxvt_ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id);

          if (pty)
            {
              delete *pty;
              ptys.erase (pty);
            }
        }
      else
        break;
    }

  // destroy all ptys
  for (rxvt_ptytty **i = ptys.end (); i-- > ptys.begin (); )
    delete *i;
}

void rxvt_ptytty_server ()
{
  int sv[2];

  if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv))
    rxvt_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n");

  pid = fork ();

  if (pid < 0)
    rxvt_fatal ("could not create pty/sessiondb helper process, aborting.\n");

  if (pid)
    {
      // client, urxvt
      sock_fd = sv[0];
      close (sv[1]);
      fcntl (sock_fd, F_SETFD, FD_CLOEXEC);
    }
  else
    {
      // server, pty-helper
      sock_fd = sv[1];

      for (int fd = 0; fd < 1023; fd++)
        if (fd != sock_fd)
          close (fd);

      serve ();
      _exit (EXIT_SUCCESS);
    }
}
#endif

// a "factory" *g*
rxvt_ptytty *
rxvt_new_ptytty ()
{
#if PTYTTY_HELPER
  if (pid > 0)
    // use helper process
    return new rxvt_ptytty_proxy;
  else
#endif
    return new rxvt_ptytty_unix;
}

/*----------------------- end-of-file (C source) -----------------------*/

Revision:	1.48
Committed:	Thu Jan 19 10:44:44 2006 UTC (18 years, 4 months ago) by ayin
Content type:	text/plain
Branch:	MAIN
Changes since 1.47:	+6 -26 lines
Log Message:	* empty log message *
#	Content
1	/---------------------------------C----------------------------------
2	* File: ptytty.C
3	----------------------------------------------------------------------
4	*
5	* All portions of code are copyright by their respective author/s.
6	* Copyright (c) 1999-2001 Geoff Wing <gcw@pobox.com>
7	* Copyright (c) 2004-2006 Marc Lehmann <pcg@goof.com>
8	*
9	* This program is free software; you can redistribute it and/or modify
10	* it under the terms of the GNU General Public License as published by
11	* the Free Software Foundation; either version 2 of the License, or
12	* (at your option) any later version.
13	*
14	* This program is distributed in the hope that it will be useful,
15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17	* GNU General Public License for more details.
18	*
19	* You should have received a copy of the GNU General Public License
20	* along with this program; if not, write to the Free Software
21	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22	---------------------------------------------------------------------/
23
24	#include "../config.h" /* NECESSARY */
25	#include "rxvt.h"
26
27	#include <cstdlib>
28	#include <cstring>
29
30	#include <sys/types.h>
31	#include <sys/socket.h>
32	#include <unistd.h>
33	#include <fcntl.h>
34
35	#ifdef HAVE_SYS_IOCTL_H
36	# include <sys/ioctl.h>
37	#endif
38	#if defined(PTYS_ARE_PTMX) && defined(HAVE_SYS_STROPTS_H)
39	# include <sys/stropts.h> /* for I_PUSH */
40	#endif
41	#ifdef HAVE_ISASTREAM
42	# include <stropts.h>
43	#endif
44	#if defined(HAVE_PTY_H)
45	# include <pty.h>
46	#elif defined(HAVE_LIBUTIL_H)
47	# include <libutil.h>
48	#elif defined(HAVE_UTIL_H)
49	# include <util.h>
50	#endif
51
52	#include <cstdio>
53	#include <grp.h>
54
55	#include "rxvtutil.h"
56	#include "fdpass.h"
57	#include "ptytty.h"
58
59	/////////////////////////////////////////////////////////////////////////////
60
61	/* ------------------------------------------------------------------------- *
62	* GET PSEUDO TELETYPE - MASTER AND SLAVE *
63	* ------------------------------------------------------------------------- */
64	/*
65	* Returns pty file descriptor, or -1 on failure
66	* If successful, ttydev is set to the name of the slave device.
67	* fd_tty _may_ also be set to an open fd to the slave device
68	*/
69	static inline int
70	get_pty_streams (int fd_tty, char *ttydev)
71	{
72	#ifdef NO_SETOWNER_TTYDEV
73	int pfd;
74
75	# if defined(PTYS_ARE_GETPT)
76	pfd = getpt();
77	# elif defined(PTYS_ARE_POSIX)
78	pfd = posix_openpt (O_RDWR);
79	# else
80	pfd = open ("/dev/ptmx", O_RDWR \| O_NOCTTY, 0);
81	# endif
82	if (pfd >= 0)
83	{
84	if (grantpt (pfd) == 0 /* change slave permissions */
85	&& unlockpt (pfd) == 0)
86	{ /* slave now unlocked */
87	ttydev = strdup (ptsname (pfd)); / get slave's name */
88	return pfd;
89	}
90
91	close (pfd);
92	}
93	#endif
94
95	return -1;
96	}
97
98	static inline int
99	get_pty_openpty (int fd_tty, char *ttydev)
100	{
101	#ifdef PTYS_ARE_OPENPTY
102	int pfd;
103	int res;
104	char tty_name[sizeof "/dev/pts/????\0"];
105
106	res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
107	if (res != -1)
108	{
109	*ttydev = strdup (tty_name);
110	return pfd;
111	}
112	#endif
113
114	return -1;
115	}
116
117	static inline int
118	get_pty__getpty (int fd_tty, char *ttydev)
119	{
120	#ifdef PTYS_ARE__GETPTY
121	int pfd;
122
123	*ttydev = _getpty (&pfd, O_RDWR \| O_NONBLOCK \| O_NOCTTY, 0622, 0);
124	if (*ttydev != NULL)
125	return pfd;
126	#endif
127
128	return -1;
129	}
130
131	static inline int
132	get_pty_ptc (int fd_tty, char *ttydev)
133	{
134	#ifdef PTYS_ARE_PTC
135	int pfd;
136
137	if ((pfd = open ("/dev/ptc", O_RDWR \| O_NOCTTY, 0)) >= 0)
138	{
139	*ttydev = strdup (ttyname (pfd));
140	return pfd;
141	}
142	#endif
143
144	return -1;
145	}
146
147	static inline int
148	get_pty_clone (int fd_tty, char *ttydev)
149	{
150	#ifdef PTYS_ARE_CLONE
151	int pfd;
152
153	if ((pfd = open ("/dev/ptym/clone", O_RDWR \| O_NOCTTY, 0)) >= 0)
154	{
155	*ttydev = strdup (ptsname (pfd));
156	return pfd;
157	}
158	#endif
159
160	return -1;
161	}
162
163	static inline int
164	get_pty_numeric (int fd_tty, char *ttydev)
165	{
166	#ifdef PTYS_ARE_NUMERIC
167	int pfd;
168	int idx;
169	char c1, c2;
170	char pty_name[] = "/dev/ptyp???";
171	char tty_name[] = "/dev/ttyp???";
172
173	c1 = &(pty_name[sizeof (pty_name) - 4]);
174	c2 = &(tty_name[sizeof (tty_name) - 4]);
175
176	for (idx = 0; idx < 256; idx++)
177	{
178	sprintf (c1, "%d", idx);
179	sprintf (c2, "%d", idx);
180
181	if (access (tty_name, F_OK) < 0)
182	{
183	idx = 256;
184	break;
185	}
186
187	if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) >= 0)
188	{
189	if (access (tty_name, R_OK \| W_OK) == 0)
190	{
191	*ttydev = strdup (tty_name);
192	return pfd;
193	}
194
195	close (pfd);
196	}
197	}
198	#endif
199
200	return -1;
201	}
202
203	static inline int
204	get_pty_searched (int fd_tty, char *ttydev)
205	{
206	#ifdef PTYS_ARE_SEARCHED
207	# ifndef PTYCHAR1
208	# define PTYCHAR1 "pqrstuvwxyz"
209	# endif
210	# ifndef PTYCHAR2
211	# define PTYCHAR2 "0123456789abcdef"
212	# endif
213	int pfd;
214	const char c1, c2;
215	char pty_name[] = "/dev/pty??";
216	char tty_name[] = "/dev/tty??";
217
218	for (c1 = PTYCHAR1; *c1; c1++)
219	{
220	pty_name[ (sizeof (pty_name) - 3)] =
221	tty_name[ (sizeof (pty_name) - 3)] = *c1;
222
223	for (c2 = PTYCHAR2; *c2; c2++)
224	{
225	pty_name[ (sizeof (pty_name) - 2)] =
226	tty_name[ (sizeof (pty_name) - 2)] = *c2;
227
228	if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) >= 0)
229	{
230	if (access (tty_name, R_OK \| W_OK) == 0)
231	{
232	*ttydev = strdup (tty_name);
233	return pfd;
234	}
235
236	close (pfd);
237	}
238	}
239	}
240	#endif
241
242	return -1;
243	}
244
245	static int
246	get_pty (int fd_tty, char *ttydev)
247	{
248	int pfd;
249
250	if ((pfd = get_pty_streams (fd_tty, ttydev)) != -1
251	\|\| (pfd = get_pty_openpty (fd_tty, ttydev)) != -1
252	\|\| (pfd = get_pty__getpty (fd_tty, ttydev)) != -1
253	\|\| (pfd = get_pty_ptc (fd_tty, ttydev)) != -1
254	\|\| (pfd = get_pty_clone (fd_tty, ttydev)) != -1
255	\|\| (pfd = get_pty_numeric (fd_tty, ttydev)) != -1
256	\|\| (pfd = get_pty_searched (fd_tty, ttydev)) != -1)
257	return pfd;
258
259	return -1;
260	}
261
262	/----------------------------------------------------------------------/
263	/*
264	* Returns tty file descriptor, or -1 on failure
265	*/
266	static int
267	get_tty (char *ttydev)
268	{
269	return open (ttydev, O_RDWR \| O_NOCTTY, 0);
270	}
271
272	/----------------------------------------------------------------------/
273	/*
274	* Make our tty a controlling tty so that /dev/tty points to us
275	*/
276	static int
277	control_tty (int fd_tty)
278	{
279	setsid ();
280
281	#if defined(PTYS_ARE_PTMX) && defined(I_PUSH)
282	/*
283	* Push STREAMS modules:
284	* ptem: pseudo-terminal hardware emulation module.
285	* ldterm: standard terminal line discipline.
286	* ttcompat: V7, 4BSD and XENIX STREAMS compatibility module.
287	*
288	* After we push the STREAMS modules, the first open () on the slave side
289	* (i.e. the next section between the dashes giving us "tty opened OK")
290	* should make the "ptem" (or "ldterm" depending upon either which OS
291	* version or which set of manual pages you have) module give us a
292	* controlling terminal. We must already have close ()d the master side
293	* fd in this child process before we push STREAMS modules on because the
294	* documentation is really unclear about whether it is any close () on
295	* the master side or the last close () - i.e. a proper STREAMS dismantling
296	* close () - on the master side which causes a hang up to be sent
297	* through - Geoff Wing
298	*/
299	# ifdef HAVE_ISASTREAM
300	if (isastream (fd_tty) == 1)
301	# endif
302	{
303	ioctl (fd_tty, I_PUSH, "ptem");
304	ioctl (fd_tty, I_PUSH, "ldterm");
305	ioctl (fd_tty, I_PUSH, "ttcompat");
306	}
307	#endif
308
309	ioctl (fd_tty, TIOCSCTTY, NULL);
310
311	int fd = open ("/dev/tty", O_WRONLY);
312	if (fd < 0)
313	return -1; /* fatal */
314
315	close (fd);
316
317	return 0;
318	}
319
320	void
321	rxvt_ptytty::close_tty ()
322	{
323	if (tty < 0)
324	return;
325
326	close (tty);
327	tty = -1;
328	}
329
330	bool
331	rxvt_ptytty::make_controlling_tty ()
332	{
333	return control_tty (tty) >= 0;
334	}
335
336	void
337	rxvt_ptytty::set_utf8_mode (bool on)
338	{
339	#ifdef IUTF8
340	if (pty < 0)
341	return;
342
343	struct termios tio;
344
345	if (tcgetattr (pty, &tio) != -1)
346	{
347	tcflag_t new_cflag = tio.c_iflag;
348
349	if (on)
350	new_cflag \|= IUTF8;
351	else
352	new_cflag &= ~IUTF8;
353
354	if (new_cflag != tio.c_iflag)
355	{
356	tio.c_iflag = new_cflag;
357	tcsetattr (pty, TCSANOW, &tio);
358	}
359	}
360	#endif
361	}
362
363	/////////////////////////////////////////////////////////////////////////////
364
365	#ifndef NO_SETOWNER_TTYDEV
366	static struct ttyconf {
367	gid_t gid;
368	mode_t mode;
369
370	ttyconf ()
371	{
372	#ifdef TTY_GID_SUPPORT
373	struct group *gr = getgrnam ("tty");
374
375	if (gr)
376	{ /* change group ownership of tty to "tty" */
377	mode = S_IRUSR \| S_IWUSR \| S_IWGRP;
378	gid = gr->gr_gid;
379	}
380	else
381	#endif /* TTY_GID_SUPPORT */
382	{
383	mode = S_IRUSR \| S_IWUSR \| S_IWGRP \| S_IWOTH;
384	gid = 0;
385	}
386	}
387	} ttyconf;
388
389	/////////////////////////////////////////////////////////////////////////////
390
391	void
392	rxvt_ptytty_unix::privileges (rxvt_privaction action)
393	{
394	if (!name \|\| !*name)
395	return;
396
397	if (action == SAVE)
398	{
399	chown (name, getuid (), ttyconf.gid); /* fail silently */
400	chmod (name, ttyconf.mode);
401	# ifdef HAVE_REVOKE
402	revoke (name);
403	# endif
404	}
405	else
406	{ /* action == RESTORE */
407	chmod (name, RESTORE_TTY_MODE);
408	chown (name, 0, ttyconf.gid);
409	}
410	}
411	#endif
412
413	rxvt_ptytty_unix::rxvt_ptytty_unix ()
414	{
415	pty = tty = -1;
416	name = 0;
417	#if UTMP_SUPPORT
418	cmd_pid = 0;
419	#endif
420	}
421
422	rxvt_ptytty_unix::~rxvt_ptytty_unix ()
423	{
424	#if UTMP_SUPPORT
425	logout ();
426	#endif
427	put ();
428	}
429
430	void
431	rxvt_ptytty_unix::put ()
432	{
433	#ifndef NO_SETOWNER_TTYDEV
434	privileges (RESTORE);
435	#endif
436
437	if (pty >= 0) close (pty);
438	close_tty ();
439	free (name);
440
441	pty = tty = -1;
442	name = 0;
443	}
444
445	bool
446	rxvt_ptytty_unix::get ()
447	{
448	/* get master (pty) */
449	if ((pty = get_pty (&tty, &name)) < 0)
450	return false;
451
452	fcntl (pty, F_SETFL, O_NONBLOCK);
453
454	/* get slave (tty) */
455	if (tty < 0)
456	{
457	#ifndef NO_SETOWNER_TTYDEV
458	privileges (SAVE);
459	#endif
460
461	if ((tty = get_tty (name)) < 0)
462	{
463	put ();
464	return false;
465	}
466	}
467
468	return true;
469	}
470
471	#if PTYTTY_HELPER
472
473	static int sock_fd;
474	static int pid;
475
476	struct command
477	{
478	enum { get, login, destroy } type;
479
480	rxvt_ptytty *id;
481
482	bool login_shell;
483	int cmd_pid;
484	char hostname[512]; // arbitrary, but should be plenty
485	};
486
487	struct rxvt_ptytty_proxy : zero_initialized, rxvt_ptytty
488	{
489	rxvt_ptytty *id;
490
491	~rxvt_ptytty_proxy ();
492
493	bool get ();
494	void login (int cmd_pid, bool login_shell, const char *hostname);
495	};
496
497	bool
498	rxvt_ptytty_proxy::get ()
499	{
500	command cmd;
501
502	cmd.type = command::get;
503
504	write (sock_fd, &cmd, sizeof (cmd));
505
506	if (read (sock_fd, &id, sizeof (id)) != sizeof (id))
507	rxvt_fatal ("protocol error while creating pty using helper process, aborting.\n");
508
509	if (!id)
510	return false;
511
512	if ((pty = rxvt_recv_fd (sock_fd)) < 0
513	\|\| (tty = rxvt_recv_fd (sock_fd)) < 0)
514	rxvt_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n");
515
516	return true;
517	}
518
519	void
520	rxvt_ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname)
521	{
522	command cmd;
523
524	cmd.type = command::login;
525	cmd.id = id;
526	cmd.cmd_pid = cmd_pid;
527	cmd.login_shell = login_shell;
528	strncpy (cmd.hostname, hostname, sizeof (cmd.hostname));
529
530	write (sock_fd, &cmd, sizeof (cmd));
531	}
532
533	rxvt_ptytty_proxy::~rxvt_ptytty_proxy ()
534	{
535	command cmd;
536
537	cmd.type = command::destroy;
538	cmd.id = id;
539
540	write (sock_fd, &cmd, sizeof (cmd));
541	}
542
543	static
544	void serve ()
545	{
546	command cmd;
547	vector<rxvt_ptytty *> ptys;
548
549	while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command))
550	{
551	if (cmd.type == command::get)
552	{
553	// -> id ptyfd ttyfd
554	cmd.id = new rxvt_ptytty_unix;
555
556	if (cmd.id->get ())
557	{
558	write (sock_fd, &cmd.id, sizeof (cmd.id));
559	ptys.push_back (cmd.id);
560
561	rxvt_send_fd (sock_fd, cmd.id->pty);
562	rxvt_send_fd (sock_fd, cmd.id->tty);
563	}
564	else
565	{
566	delete cmd.id;
567	cmd.id = 0;
568	write (sock_fd, &cmd.id, sizeof (cmd.id));
569	}
570	}
571	else if (cmd.type == command::login)
572	{
573	#if UTMP_SUPPORT
574	if (find (ptys.begin (), ptys.end (), cmd.id))
575	{
576	cmd.hostname[sizeof (cmd.hostname) - 1] = 0;
577	cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname);
578	}
579	#endif
580	}
581	else if (cmd.type == command::destroy)
582	{
583	rxvt_ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id);
584
585	if (pty)
586	{
587	delete *pty;
588	ptys.erase (pty);
589	}
590	}
591	else
592	break;
593	}
594
595	// destroy all ptys
596	for (rxvt_ptytty **i = ptys.end (); i-- > ptys.begin (); )
597	delete *i;
598	}
599
600	void rxvt_ptytty_server ()
601	{
602	int sv[2];
603
604	if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv))
605	rxvt_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n");
606
607	pid = fork ();
608
609	if (pid < 0)
610	rxvt_fatal ("could not create pty/sessiondb helper process, aborting.\n");
611
612	if (pid)
613	{
614	// client, urxvt
615	sock_fd = sv[0];
616	close (sv[1]);
617	fcntl (sock_fd, F_SETFD, FD_CLOEXEC);
618	}
619	else
620	{
621	// server, pty-helper
622	sock_fd = sv[1];
623
624	for (int fd = 0; fd < 1023; fd++)
625	if (fd != sock_fd)
626	close (fd);
627
628	serve ();
629	_exit (EXIT_SUCCESS);
630	}
631	}
632	#endif
633
634	// a "factory" g
635	rxvt_ptytty *
636	rxvt_new_ptytty ()
637	{
638	#if PTYTTY_HELPER
639	if (pid > 0)
640	// use helper process
641	return new rxvt_ptytty_proxy;
642	else
643	#endif
644	return new rxvt_ptytty_unix;
645	}
646
647	/----------------------- end-of-file (C source) -----------------------/
648